Spectroscopic analyzers are used in a variety of applications. For example, infrared analyzers are used to monitor various fluids such as dairy products, fuels, oils, lubricants, in addition to solids, aerosols, gases, and the like.
The primary components of the applicant's infrared analyzer include a source of infrared radiation, typically a filament, which directs infrared radiation through a sample held in a cell. After passing through the sample, the infrared radiation enters an analyzer including a wedge conditioner, a reflective grating, and a detector assembly. The output of the detector assembly is input to a processor programmed with algorithms used to determine the different components of the sample. The results can be depicted on a display linked to the processor.
Absorption of certain infrared frequencies by the sample is indicative of different components in the sample. See U.S. Pat. Nos. 6,289,149; 5,856,870; and U.S. patent application Ser. No. 11/347,482 all incorporated herein by this reference. Additional prior art includes U.S. Pat. Nos. 5,470,757 and 5,764,355 also incorporated herein by this reference.
Various sample heads or cells are known. In one example, a syringe is used to inject a small quantity of oil into a sample cell. Typically, such a cell has ˜100 microns thickness. In this case, since the sample cell is filled and not accessible for cleaning, solvent must be introduced in to the cell to remove any remaining sample. The solvent must then be removed from the sample cell which requires forced air. This entire process requires solvent processes to ensure the cell is properly cleaned, and significant time to perform the procedure properly. Moreover, in the field, technicians may not have the skill or time required in order to ensure a proper cleaning process.